Apparatus for the continuous heat treatment of runing yarns

ABSTRACT

Apparatus for the continuous heat treatment of a number of running yarns, tows, threads, strands or the like with saturated steam requiring a corresponding number of straight pressure pipes as individual heating chambers with feed inlet means for the steam and including a corresponding number of pressure locking means having a variable throttle cross-section at each of the inlet and outlet ends of the heating chambers so that the heating chambers are individually supplied with the steam and the yarns can be individually reintroduced in the event of breakage. The pressure locking means is preferably constructed with a special labyrinth seal.

United States Patent Ostertag et al.

[ Dec. 18, 1973 APPARATUS FOR THE CONTINUOUS HEAT TREATMENT OF RUNINGYARNS Inventors: Karl Ostertag, Elsenfeld; Heinrich Nilgens, Erlenbach;Herbert Scheiber, Kleinwallstadt, all of Germany Assignee: AkzonaIncorporated, Asheville,

Filed: Apr. 21, 1972 Appl. No: 246,326

Foreign Application Priority Data May 4, 1971 Germany P 21 21 843.9

US. Cl. 34/155, 34/242 Int. Cl. F26b 25/00 Field of Search 34/154, 155,151, 34/156, 152, 242, I5, 92; 68/175, 5; 28/61, 62

References Cited UNITED STATES PATENTS SPINNING UNITS W. ll

2,005,580 6/1935 l-erre 34/242 2,317,448 4/1943 Dreyfus et al. 34/2422,380,422 7/l945 Frank 3.4/242 Primary Examiner-Kenneth W. SpragueAssistant Examiner.lames C. Yeung Att0rney-J0hn H. Shurtleff [5 7]ABSTRACT Apparatus for the continuous heat treatment of a number ofrunning yarns, tows, threads, strands or the like with saturated steamrequiring a corresponding number of straight pressure pipes asindividual heating chambers with feed inlet means for the steam andincluding a corresponding number of pressure locking means having avariable throttle cross-section at each of the inlet and outlet ends ofthe heating chambers so that the heating chambers are individuallysupplied with the steam and the yarns can be individually reintroducedin the event of breakage. The pressure locking means is preferablyconstructed with a special labyrinth seal.

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APPARATUS FOR THE CONTINUOUS HEAT TREATMENT OF RUNING YARNS Thisinvention generally relates to apparatus for the continuous heattreatment of agroup or bundle of synthetic filaments, continuous yarnsor the like, especially spun tows of filaments for industrial purposes,at temperatures above 100C. and in substantially sealed treatmentchambers.

In order to obtain better strength, elongation and shrinkage properties,synthetic filaments of thermoplastic fiber-forming polymers as endlessyarns, strands or tows are normally subjected after spinning to aheattreatment and stretching process followed by heat stabilization orpartial to complete shrinkage.

Known arrangements for carrying out the heat treatment include steamingchambers through which the tows or multifilament yarns delivered fromthe spinning stations, having been divided up into individual yarn Igroups or thread bundles, are guided in the form of such groups orbundles laterally separated at a short distance from one another. Thelength of the steaming chambers and hence the average residence time ofthe tows or yarns in the treatment zone is governed by the processconditions, more particularly by the required stretching rate, by thepolymer material, by the denier or size of the monofilaments, by thecross section of the yarn and by the properties of the treatment medium.For example the length of the steaming chamber or treatment zone amountsto approximately 10 meters in,

cases where a nylon tow of 140 filaments with a denier or yarn size of940 dtex is stretched in a ratio of 125.] at a take-off rate from thestretching rolls of 200 meters per minute, the steaming chamber beingheated to 250C. with highly superheated low-pressure steam. The nylontow or yarn is passed through the steaming zone with a residence time ofapproximately 'r 3 seconds, having reached a temperature ofapproximately 225C. at its surface.

On account of their large geometrical dimensions, the steaming chamberswhich are preferably made of rust proof steel alloys involve aconsiderable expense. They also occupy a very large amount of space andcan readily cause a bottleneck to the economically interesting anddesirable production rates which may otherwise be achieved with modernstretching or drawing apparatus. The length of the steaming chamber isessentially attributable to the low heat-transfer coefficients betweenthe treatment medium, i.e. superheated steam, and the travelling yarn ortow. The values which can be achieved for the heat-transfer coefficientsare in the range from 10 to 100 kcal/m hC. These values are governedboth by the temperature and by the flow rates of the treatment medium tothe extent that higher tempera-tures increase the radiation componentwhile higher rates of flow increase the convection component of the heattransfer coefficient. Thus, a value of 43 kcal/m hC. is quoted forexample by Mieck Faserforschung and Textiltechriik," 19, pages 181-187(1968), for the heat-transfer coefficient a.

The steaming or heat treatment chamber through which the group of yarnsor tows is guided is covered by a hood to avoid steam losses and toprevent the conditions prevailing therein from being adversely affectedby the escaping steam. Accordingly, in the event of breakage of anindividual yarn for example, it is not normal for this yarn to beimmediately reintroduced because the yarn cannot be threaded in orguided through the apparatus without opening the cover of the steamingchamber. The treatment process for the entire group of yarns is onlyinterrupted after an economically reasonable minimum number of breaks,and the broken yarns are then reintroduced together. This results invarrying quantities of waste and stoppage times attributable to thedevice.

This disadvantage also occurs for example in the arrangement disclosedin Swiss Pat. No. 488,844 in which a number of thread-like materialsarranged parallel to one another can be treated under elevated pressurein a single container or chamber.

in order to reduce the amount of space occupied by the heatingapparatus, the heat-transfer coefficients between the treatment mediumand the filamentary mate-. rial being treated could be improved.According to British Pat. Nos. 1,037,935 and 1,171,263, it isparticularly favorable in terms of process technology to use a heatedsubstantially vaporous treatment medium under excess pressure, forexample saturated steam with temperatures above C., instead of thehighly superheated low-pressure steam which only allows moderateheat-transfer coefficients. Due to condensation of the steam, the timerequired to heat the filament to the stretching temperature isconsiderably reduced by virtue of the fact that the heat-transfercoefficients are 100 times higher, in addition to which the stretchingforces required and/or the requisite stretching temperatures are reducedbecause of the plasticizing effect of the condensate on the filaments.

So far as the apparatus is concerned, however, the application of suchexcess pressure means that any individual treatment zone must bedesigned for at least the excess pressure of the vaporous or gaseoustreatment medium and that pressure locks must be provided at the inletand outlet ends of such treatment zone through which the yarn, tow orthe like is continuously introduced and discharged, and such pressurelocks must effectively prevent pressure losses through dissipation ofthe treatment medium from the treatment zone to the surroundingatmosphere.

Pressure locks in treatment zones for textile yarns, fabric webs or thelike are shown in various known embodiments, but unfortunately theyeither do not allow the textile material to be continuously treated (US.Pat. No. 3,140,594) or are only suitable when there are very smallpressure differences between the textile material being treated and theoutside atmosphere. Other known devices are adaptable only to web-likesheets or fabrics (US. Pat. Nos. 3,032,890; 3,126,724 and 3,137,151). Instill another known pressure lock (US. Pat. No. 3,213,470), severalpressure cells filled with superheated steam are arranged one behind theother in series, the cells being separated by plates and joined togetherby small openings or holes with limited flow cross-sections for passageof a textile yarn. By reason of the steam barrier, it is possible tomaintain the pressure of the superheated steam in the treatment zonelocated between the pressure locks. The disadvantage of this apparatusresides in the fact that the constant throttle cross-sections betweenthe pressure cells makes it difficult to reintroduce or properly threadthe yarn, especially when the length of the treatment chamber betweenthe pressure locks is in excess of several meters. For this reason, suchknown pressure locks are not at all suitable for heat treatmentapparatus in which yarn breakage occurs quite frequently, i.e.,especially when such heat treatment is required for a plurality ofyarns, towsor the like issuing from spinning units and- [or incombination with stretching or drawing devices.

One object of the present invention is to obviate the disadvantagesarising in conventional heat treatment apparatus required for thecontinuous processing of a number of running yarns, tows, threads,strands or similar bundles of filamentary textile materials,particularly to provide apparatus occupying aslittle space as possiblewhile being designed in such a way that when one yarn or group offilaments breaks, it can be reintroduced or rethreaded in the samerunning position and again subjected to the heat treatment processindependently of the remaining yarns or groups of filaments.

Another object of the invention is to divide a common heat treatmentchamber into a number of individual, parallel heating zones which canreceive: steam or another heating medium independently of one anotherand which permit rethreading of a running yarn independently of oneanother.

Yet another object of the invention is to provide a heat treatmentapparatus in which a plurality of individual heating chambers can beefficiently maintained under relatively high pressures so as to achievecorrespondingly high heat transfer coefficients but with as littlepressure loss as possible while a continuous yarn,

tow or the like is conducted through each heating chamber.

Still another object of the invention is to provide a heat treatmentapparatus for a plurality of individual yarns or tows, especially asthey are spun from a thermoplastic fiber-forming polymer and stretchedby com ventional feed and draw'means, whereby each individual yarn ortow is continuously transported through its own individual treatmentchamber at much higher speeds and with lower residence times and/or heattreatment temperature.

These and other objects and advantages of the invention will become moreapparent upon consideration of the following detailed specification.

in accordance with the present invention, it has now been found thathighly improved results can be achieved in a heat treatment apparatusfor processing a plurality of filamentary bundles as a yarn, tow or thelike with a vaporous heatingmedium at temperatures above 100C, andpreferably with saturated steam under superatmospheric pressure. by thecombination which comprises a plurality of substantially closedelongated treatment chambers corresponding in number to the number offilamentary bundles being treated, each chamber being substantially inthe form of a straight pressure pipe over most of its length, all ofsaid pipes being arranged at lateral intervals apart from one another onsubstantially parallel axes, separate feed pipe means for introductionof the vaporous heating 1 medium into each treatment chamber, and twoflow duct members including pressure locking means for each treatmentchamber, one being arranged at the inlet end and the other at the outletend thereof so that each is in direct fluid connection with thetreatment chamber.

More particularly, it has been found most desirable to provide eachpressure locking means with at least one valve throttling element whichis displaceably arranged in the flow duct path for variation of thethrottle cross-section, i.e., so that the flow cross-section of the ductcarrying the yarn or tow can be changed according to different positionsof the valve element between an effective minimum working opening orcross-section up to a maximum cross-section which preferably correspondsto the completely open or free cross-section of the flow duct.

in this preferred embodiment of the apparatus according to theinvention, the flow duct members define a flowpath through which thevaporous heating medium leaves the treatment chamber and through whichthe filamentary material to be treated is introduced into or dischargedfrom the treatment chamber, and the pressure locking means preferablyincludes a plurality of rotatably mounted valve cylinders, especiallyabout four to six valve cylinders, which penetrate at about right anglesinto said flow duct path while being arranged in a row one behind theother on parallel axes of rotation lying in about the same plane, eachvalve cylinder being variably recessed at the point of intersection withthe flow duct to alter the cross-section of the flow path upon rotationof the valve cylinder.

For varying the throttle cross-section, each valve cylinder can beconstructed to provide a first arcuate or partially cylindrical recesson one side thereof about as deep as the diameter of the flow duct pathso as to provide a maximum cross-section of the flow path when the valvecylinder is in its completely open position. This first recess isadjoined at an acute angle by a narrower slot recess or openingextending from the first recess at a point spaced sufficiently inwardlyfrom the outer circumference of the valve cylinder to provide a smallworking opening at the common junction of the two recesses.

in one especially advantageous embodiment, the valve cylinders of thepressurelock are larger in diameter and preferably about twice as largein diameter as the open path of the flow duct. The valve cylinders arearranged in such a way that the axis of the flow duct of the pressurelock does not intersect the plane in which the axies of the cylindersare arranged, i.e. so that these two planes are offset and parallel toeach other.

By means of the apparatus according to the invention, it is possiblecontinuously to treat a group of continuous yarns or tows correspondingin number to the number of treatment chambers provided. With the help ofthe pressure locks at the inlet and outlet ends of each heat treatmentchamber, the filamentary bundle to be treated is introduced into thedischarged from the treatment chamber and transported therethroughsubstantially free of any contact. The throttle effect of the valvecylinders provided with the recesses, whose free or open geometricalcross-section should be approximately 2.0 to 3.5 times and preferablyfrom 2.5 to 3.0 times larger than the yarn cross-section, is extremelyfavorable and enables the apparatus to be used with a heated,substantially vaporous treatment medium under excess or superatmosphericpressure, for example with a dry saturated steam as the heating vapor.

in an especially preferred embodiment of the apparatus according to theinvention, at least one turbulence or eddy chamber is arranged betweentwo adjacent valve cylinders along the flow duct path of the pressurelocks. These turbulence chambers, which are generally known inthemselves, are formed as a preferably cylindrical bore at least partlyintersecting the flow duct path of the pressure lock, e.g., by usingseveral parallel bores extending substantially perpendicularly of theflow duct and preferably being substantially equal in diameter to thediameter of the valve cylinders. For reasons of manufacture, the valvecylinders and the turbulence chambers are preferably arranged in such away that their axes lie in planes that are parallel to one another andsymmetrical to the axis of the flow duct, e.g., off-set to either sideof the flow duct path in each pressure locking means.

By virtue of this combined arrangement of the valve cylinders havingvariable and adjustable throttle crosssections with the turbulencechambers, a considerable flow resistance is provided against the leakageflow of the vaporous heating medium due to the turbulent flow conditionscreated by the labyrinth system of flow paths, so that the pressureprevailing inside the individual yarn treatment chambers can bemaintained with minimal steam losses. The leakage losses are no greaterthan those found in the above-described steaming or heating chamberswhich operate in the absence of pressure or only at a very slight excesspressure.

In still a further development of the apparatus according to theinvention, the valve throttling elements or cylinders of the pressurelocks are arranged for displacement or rotation in such a way that thedifferent or variable throttle cross-sections introduced by these valvesinto the flow duct path are simultaneously or synchronously adjustableeither manually or by positive power transmission means, preferably inthe form of paired gear wheels meshing with one another andinterconnecting adjacent valves for synchronous rotation. These pairedgear wheels can be driven for example by means of a rack which is movedby a double-acting pneumatic or hydraulic cylinder or any similarlyuseful drive means.

One embodiment of the apparatus according to the invention for heattreatment of a group of filamentary bundles or yarns is described by wayof example in the following portion or the specification taken withreference to the accompanying drawings, wherein:

FIG. 1 is an elevation of the apparatus according to the invention,partly in longitudinal section;

FIG. 2 is a cross-section on the line 22 of FIG. 1

passing through a plurality of yarn treatment chambers surrounded by acommon heating box;

FIG. 3 is a partial cross-section through one example of a pressure lockof the invention with operating means for the adjustable valvecylinders;

FIG. 4 is an elevation of the end plate of the apparatus with severalyarn treatment chambers being combined to form a single unit;

FIG. 5 is a plan view of the pressure locks of the apparatus combined toform a single unit;

FIG. 6 is a longitudinal section through the flow duct of a pressurelock with the yarn inserted and the labyrinths closed;

FIG. 7 is a longitudinal section through the flow duct ofa pressure lockin the threading position with the labyrinths open;

FIG. 8 is a cross-section through the flow duct of a pressure lock onthe line 8-8 of FIG. 6;

FIG. 9 is a cross-section through the flow duct on line 99 of FIG. 7;

FIGS. 10 to show valve cylinders of the pressure lock in differentpositions both in elevation and in corresponding cross-section (on alarger scale);

FIG. 16 is a longitudinal section through a pressure lock according toanother embodiment of the invention in the form of a stationarydismountable and manually adjustable labyrinth system of flow paths; and

FIG. 17 is a cross-section through the pressure lock on line l7-l7 ofFIG. 16.

A preferred embodiment of the heat treatment apparatus according to theinvention, generally denoted by the reference numeral 1, is shown partlyschematically in its overall arrangement as set forth in FIG. 1. Thisapparatus requires a number of straight tubular pressure pipes 2, i.e.,pipes which are pressure-resistant, corresponding to the number ofrunning yarns Y. These pipes are arranged at a lateral interval from oneanother and with their axes parallel to one another between the two endflanges 3. In the interests of clarity,

the pressure pipes 2 which act as the heating chambers with a lengthadapted to particular process conditions, have been shown in FIG. 1 onlyin a restricted zone in the vicinity of the flanges 3, a large centralportion having been omitted so that the feed pipes 4 through which thehot vapor or treatment medium enters the respective treatment chambersare visible only in FIG. 2. The pressure pipes 2 are surrounded by acommon heating box 5, for example in the form of a large cylindricaltube 6, closed at its ends by the flanges 3. The heating box 5 isdesigned to be heated with steam or any other suitable vaporous heatingmedium by means of the inlet line 7 and the condensate outlet line 8(FIG. 2), preferably with box 5 also maintained under the same pressureas the pipes 2 so that leakage losses of the treatment chambers 9 arenegligible. The flanges 3 of the apparatus are connected in intermediatecrossbar members 10 in which the yarn guide channels or bores 11 areprovided at suitable intervals for connection with pipes 2. Thestiffening ribs 12 together with crossbars 10 act to join flanges 3 tothe pressure locks shown in simplified form in FIG. I and generallydenoted by the reference numeral 13.

It is particularly favorable to design each individual feed pipe 4 forintroducing the vaporous heating medium separately into each treatmentchamber 9 in such a way that it can be separately shut off, i.e., bymeans of the valves 16. However, it is also desirable to provide all thefeed lines for the vaporous medium with the common regulating valve 18which is adjusted to the saturated steam pressure in the treatment zoneand which is arranged for example between the main steam line and acommon reservoir 17. Each shut-off valve 16 is preferably in the form ofa quick-closing or fastacting solenoid valve which, in the event of yarnbreakage or other disturbance of yarn supply is actuated through thecontrolling impulse of a conventional yarn monitor in order to shut offthe supply of steam and preferably to also initiate the process ofrethreading the temporarily deactivated treatment chamber. By turningthe cylinders or throttling elements 25 of the pressure locks through anangle of approximately from the closed operating position as shown inFIGS. 6 and 8 to j the open threading position of FIGS. 7 and 9, thefull cross-section of the flow duct path is opened and the throttleeffect of the lock eliminated. This operation is especially facilitatedwhere the valve cylinder diameter is twice as large as the diameter ofthe flow duct path and when the vertical interval between the flow ductaxis and that plane in which the axes of the cylinders are arranged isequal to half the diameter of the flow duct path (i.e., at a distance orinterval of approximately the radius of this flow duct path).

. The yarns, threads or tows Y are passed through these pressure locks13 as indicated by the direction of the arrows so as to be introducedinto and discharged from the treatment chambers 9 maintained underelevated pressure. Connected to the outlet end of each yarn treatingchamber 9, there is an injector 14 which, for purposes of initialthreading or in the event of yarn or tow breakage, is designed toreceive compressed air through the lateralsupply line '15 threading andtensioning the yarn while the pressure locks remain open.

The apparatus according to the invention thus greatly facilitatesathreading or rethreading operation, preferably by using a threadtransporting means in the form of a jet ejector or injector l4 fed withcompressed air. This injector is preferably automatically actuated inthe event of yarn or tow breakage for the purpose of threading orreintroducing the yarn or tow as quickly as possible. Instead of aninjector fed with compressed air, it is also possible in some cases toprovide a steam injector, in which case the superheated steam used asthe vaporous heating medium for the yarn may also be used as the workingmedium for operating the steam injector. Unfortunately, this has thedisadvantage that where the rethreading system is automatically broughtinto operation, large quantities of steam are let off into thesurrounding atmosphere. Safety measures must then be taken to preventthe operator from being scalded, e.g., by warning lights or signals aswell as baffles or the like to contain the steam.

The injector 14 can be provided between the treatment chamber 9 and thepressure lock 13, although it is particularly favorable both for reasonsof design and also for hydrodynamic reasons to provide the injector atthe outlet end of the apparatus behind the pressure lock 13. In thiscase, it can be connected to the discharge pipe 38' of the pressure lockeither tightly in fixed position or even detachably, for examplepreferably by means of a bayonet joint or quick-release coupling 14'.With this easily detached injector, it is possible to readily shift itfrom one pressure lock to another as needed, especially where its use isrelatively infrequent.

FIG. 2 is a cross-section through the yarn treatment chambers 9 and thecommon heating box 5. In this embodiment, for example, a total of sevenpressure pipes 2 are arranged parallel to and closely adjacent to oneanother. However, the pipes 2 can also be arranged offset relative toone another or in any desired pattern. All of these pressure pipes haveseparate feed pipes 4 for introduction of the vaporous treatment medium,e.g., steam. Shut-off valves 16 are provided in each of the feed pipes4, each valve being actuated through an impulse from a correspondingyarnmonitor (not shown) in the event of yarn breakage. Such yarnmonitors are quite conventional as devices which rest upon or senseindividual'yarns as they run through a prescribed path and then actuatea switch or otherwise transmit an impulse when the yarn leaves theprescribed path, e.g., due to breakage or other loss of the thread.

The feed pipes 4 are in turn connected to a steam accumulator orreservoir 17 which is in fluid communication with the steam main orsupply source through a pressure regulated reducing valve 18. As shownin FIG. 2, the feed line 7 of the outer heating box of the apparatus isalso connected to the steam reservoir 17 and a pressure detector orsensor 19 inside the heating box 5 transmits a regulating impulse to thereducing valve 18 through a suitable pressure convertor 20 ortranslating control device operating with ideal value/true valuecomparison. Such pressure regulating means are quite conventional formaintaining a prescribed pressure and therefore are shown schematicallyin the drawing.

As generally illustrated herein, it is particularly advantageous toprovide each treatment chamber 9 for an individual bundle of filament asa straight pressure pipe capable of being substantially closed orthrottled at both ends while placing all of these chambers 9 or pipes 2whithin a'common closed heating box 5, preferably as a large cylinder ortube, thereby permitting this box or enclosure 5 to be fed with thevaporous heating medium at both the same temperature and pressure asthat introduced into the individual treatment chambers 9. In thisparticular embodiment, the individual pressure locks 13 are eachprovided in a common block designed to be assembled according to thebuilding block principle so as to be rigidly connected to the heatingbox 5, i.e., the end flanges thereof. The yarn treatment chambers 9, aspressure pipes 2 are welded or otherwise rigidly connected to theassociated yarn inlet and yarn outlet ducts 10 of the pressure locks.All of these elements, i.e., the yarn treatment chambers, heated box,pressure locks and flow duct members, including even the injector, arethus preferably arranged on a common axis as indicated in FIG. 1.

The advantage of enclosing the pressure pipes 2 in box 5 is that thedissipation of heat from the walls of the treatment chambers 9 and theaccompanying increased condensation of the vaporous heating medium canbe largely avoided, and this lower condensation in chambers 9 has afavorable effect upon the quality of the yarn being treated. Because theexternal heating of the treatment chambers remains effective even duringa temporary stoppage for reintroduction of a broken yarn, during whichthe supply of vaporous heating medium is turned off, all the treatmentchambers remain at substantially the same temperature level so that theapparatus is not subjected to any thermal stressing or heat distortion.

A pressure lock I3 is shown in greater detail in FIG. 3. It consists ofthe block 21 in which the flow ducts 22 required for several pressurelocks are drilled as indicated in the longitudinal direction and arelocated behind one another in this view. The yarn or filamentarymaterial Y isintroduced into (or discharged from) the treatment chambers9 through these flow ducts which are connected for example to feed line39 and discharge ll. The block 21 also includes offset bores 23 and 24which extend perpendicularly of the flow ducts (cf. FIGS. 6 to 9). Thebores 23 are each provided with a rotatable, ground valve cylinder 25whose relatively thin stem 26 projects through the sealing plate 27 or28 and at its head carries a gear wheel 29 which is fixed for rotationwith the cylinder stem 26. As shown in FIGS. 6 and 7, the axes of thebores 23 for the cylinders 25 and the axes of the bores 24, which formthe eddy or turbulence chambers, lie respectively in parallel planesseparated by substantially the same interval from the axis of the flowduct 22, i.e. at one radius of the flow duct path.

The valve cylinders 25 and the chambers 24 function alternately alongthe flow path and the interval between the cylinder axes is selected insuch a way as to correspond to the pitch diameter of the identical gearwheels 29 which mesh with one another. The cylinders of one and the samepressure lock are guided through the sealing plate 27 or 28 on the sameside and in addition are arranged in such a way that, corresponding tothe opposite rotational movement of adjacent meshing gear wheels 29, thethrottling recesses of the cylinders are arranged symmetrically to oneanother as shown in FIG. 6 in the vicinity of the flow ducts 22 whichare to have the variable throttle cross-sections.

The gear wheels 29 are designed to be driven together through pinionmeans 30 moved by a rack 31 connected to the piston rod 32 ofadouble-acting pneumatic cylinder 33 or the like on receiving the commanor signal.close labyrinth or open labyrinth. The longitudinal movementof the rack 31 and the piston rod 32 is limited in both directions by astop 34, e.g., so as to provide a 90 rotation of the valves. The endplates 35 are used to secure the pneumatic cylinders through the locknuts 36 while the plates 37 are used to mount the stops 34 whose pinsare guided in a longitudinal groove 43 in the piston rod. In themouthpiece or nozzle 38, the yarn guide ducts 39 are provided at lateralintervals correspond to those separating the corresponding flow ducts 22with which they are interconnected. To reduce wall friction, all theyarn guide ducts 29, 11 and 9 are made with polished surfaces.

FIGS. 4 and are an elevation and plan view, respectively, of part of theapparatus with seven yarn treatment chambers assembled to form a singleunit and their associated pressure locks. However, the number of yarntreatment chambers, e.g. as steam heated pressure pipes, is not confinedto a fixed number and can be varied as required by a given spinningoperation.

In order to accommodate as many yarn treatment chambers and pressurelocks as possible together with the associated adjusting members in thesmallest possible space, the drive means for the throttle members arepreferably arranged in such a way that for adjacent pressure locks theylie alternately above the sealing plate 27 and below the sealing plate28. In addition, the pneumatic cylinders are fixed alternately to thefront and to the rear end plates 35 of the pressure locking means (cf.FIGS. 4 and 5).

In FIGS. 6 to 15, the rotatably mounted cylinders 25, near the pointwhere, they penetrate their associated flow duct 22, have a cylindricalrecess 40 equivalent in depth to the flow duct 22 so that where thethrottle members are positioned as shown in FIGS. 7 and 9, the fullcross-section of the flow duct 22 is opened and the throttle effect ofthe labyrinth system is eliminated. This open" position provides a largestraight path through each yarn treating position for threading orrethreading when the pressure and introduction of vaporous heatingmedium to the yarn treatment chamber is temporarily in an of position,e.g., in response to yarn breakage.

The arcuate recess 40 is adjoined at an acute angle by a narrowerslot-like recess 41 which is equivalent in depth to the working canal orchannel opening 42 provided at the common junction between the tworecesses. This provides a small square or rectangular opening 42 whenthe valve cylinder has been turned to a fully closed" or operatingposition (see FIGS. 6 and 8). This opening is not more than about 2 to 3times the cross-section of the yarn and offers only a slight guidingcontact to the yarn while fully throttling the flow of vapors.

The apparatus according to the invention for treating a group ofcontinuous filamentary bundles, yarns or tows which, in its preferredform, has one pressure lock with variable throttle cross-sections ateither end, can also be provided in a mechanically more simpleconstruction with pressure locks in which more or less fixed labyrinthsrestrict outflow of the treatment medium as shown in FIGS. 16 and 17.The pressure lock generally denoted by the reference numeral 50 is madeup of the lower casing member 51 with the yarn guide duct 52 machinedinto it, being connected to the flange 53 of the yarn treatment chamberor to the heating box surrounding it, and of the detachable upper casingmember 54. The upper part 54 is connected to the lower part 51 by astirrup fastening means 55 which is rotatably locked or secured inposition by the bolt 56. In the operating position, the upper part 54 ofthe pressure lock is pressed firmly onto the lower part 51 by means ofthe setscrew 57 and sealed off there. In the threading position, thissetscrew is loosened, the stirrup fastening pivoted to one side and theupper part 51 of the pressure lock removed so that, by means of aninjector mounted at the beginning of the yarn guide duct 52, the yarncan be pulled through the entire arrangement and inserted into thelabyrinth and the yarn guide 58.

The labyrinth shown in FIGS. 16 and 17 is assembled in such a way thatseveral small tubes 59 and 60 are provided one behind the otherperpendicularly of the yarn guide duct 52, the tubes 59 which areinserted into the removable upper part 54 of the pressure lock, beingshorter than the tubes 60, not quite extending to the middle of the yarnguide duct 52. The tubes 60 are also inserted, for example cemented,into the upper part 54 of the pressure lock. However, they are longerand extend into the lower part 51 of the pressure lock where they areguided into corresponding bores. In the lower region 61 which makes upabout one-third of the overall length of the tube 60, the walls of thetube 60, as shown in FIG. 17, are provided with longitudinal slots 62all of which lie in the same plane looking in the direction of yarntravel. The flow duct in the pressure lock is formed by the longitudinalslot 63 in the lower part 51 of the pressure lock. It is limited by theslot 62 in the longer tube 60 corresponding to the yarn-cross sectionand the permitted leakage losses of the treatment medium. Opposite theshorter tubes 59 in the lower part 51 of the pressure lock, there aresituated corresponding bores 64 into which the vaporous heating mediumis able to expand in exactly the same way as into the tubes themselves.This mode of operation corresponds to the turbulence or eddy chambersdescribed with reference to FIGS. 3, 6 and 7.

In order to prevent the bores 64 from being partly filled withcondensate, the bore 64 lying closest to the yarn guide duct 52 andhence closest to the yarn treatment chamber is adjoined by thecondensation pipe 65 comprising a condensation outlet (not shown), forexample a thermally-operated condensation outlet.

The apparatus according to the invention as described in the foregoingspecification has proved to be particularly suitable for the heattreatment of spun tows or yarns, in particular those of syntheticfiber-forming thermoplastic polymers. Thus, one can heat treat thoseyarns composed of nylons such as polyhexamethylene ene and many othersynthetic or artificial filamentary materials which require a continuousheat treatment of the running yarn or tow. The apparatus of theinvention is most useful in combination with conventional spinning anddrawing means where rapid heating of a large group of separatelyprocessed bundles or yarns is essential.

ln those cases where a meters long conventional steaming chamber wasused for treating a nylon tow of 140 filaments with a yarn size of 940dtex, stretched in a ratio of l:5.l, the tow could be run off only at arate of 200 meters per minute at the outlet end of the stretching ordrawing device where the steaming chamher was heated to 250C. withhighly superheated low-' pressure steam. By comparison, it was possibleby using the heating apparatus according to the present invention fortravelling or running yarns heated with steam as the treatment medium ata temperature of about 152C, corresponding to a saturated steam pressureof approximately 5.] atm., to increase the draw-off rate at the outletend ot t he stretching device to @00 meters per minute using suitabletake-off godets. The length of the heating zone was reduced to 3.5meters. The much shorter residence time of the nylon tow in the heattreatment zone was still quite sufficient for adequately heating thetow. Such results confirm the highly improved operation and thermalefficiency of the apparatus of the invention.

The invention is hereby claimed as follows:

1. Apparatus for the continuous heat treatment of a plurality offilamentary bundles as a yarn or the like with a vaporous heating mediumat temperatures above 100C, said apparatus comprising:

a plurality of substantially closed elongated treatment chamberscorresponding in number to the number of filamentary bundles beingtreated, each chamber being substantially in the form of a straightpressure pipe over most of its length, all of said pipes being arrangedat lateral intervals apart from one another on substantially parallelaxes;

separate feed pipe means for introduction of the vaporous heating mediuminto each treatment chamber; and

two flow duct members including pressure locking means for eachtreatment chamber, one duct memher being arranged at the inlet end ofsaid chamber and the other at the outlet end thereof so that each is indirect fluid connection with the treatment chamber,

said pressure locking means comprising a plurality of rotatably mountedvalve cylinders which penetrate at about right angles into the flow ductpath while being arranged in a row one behind the other on parallel axesof rotation lying in about the same plane, each valve cylinder beingvariably recessed at the point of intersection with the flow duct toalter the cross-section of the flow path upon rotation of the valvecylinder.

2. Apparatus as claimed in Claim 1 wherein four to six valve cylindersare arranged along said flow duct path for each pressure locking means.

3. Apparatus as claimed in claim 1 wherein each of said valve cylindershas a first arcuate or partially cylindrical recess on one side thereofwith a depth corresponding approximately to the diameter of the flowduct path together with an adjoining narrower slot recess extending atan acute angle from said first recess from a point spaced sufficientlyinwardly from the outer circumference of the valve cylinder to provide asmall working opening at the common junction of the two recesses.

4. Apparatus as claimed in claim 3 wherein each of said valve cylindershas a diameter which is approximately twice the diameter of the flowduct path.

5. Apparatus as claimed in claim 3 wherein the plane of the axes ofrotation of said valve cylinders is offset to one side of the axis ofthe flow duct path.

6. Apparatus as claimed in claim 4 wherein the plane of the axes ofrotation of said valve cylinders is offset to one side of the axis ofthe flow duct path at a distance of approximately the radius of saidflow duct path.

7. Apparatus as claimed in claim 3 wherein said working opening at thecommon junction of the two recesses in each valve cylinder is about 2.0to 3.5 times greater than the cross-section of the yarn being treated.

8. Apparatus as claimed in claim 1 including at least one turbulencechamber which is arranged along the flow duct path between two adjacentvalve cylinders.

9. Apparatus as claimed in claim 8 wherein each turbulence chamber isformed by a bore extending substantially perpendicularly and at leastpartly intersecting the flow duct path.

10. Apparatus as claimed in claim 9 having a plurality of said boresforming turbulence chambers alternately between adjacent valvecylinders, said turbulence chambers being substantially equal indiameter to said valve cylinders and said turbulence chambers and saidvalve cylinders being arranged with their axes lying in separateparallel planes offset and symmetrical to the axis of the flow ductpath.

1 1. Apparatus as claimed in Claim 1 including means to simultaneouslyadjust the valve cylinders of said pressure locking means between aclosed operating position and an open threading position.

12. Apparatus as claimed in claim 1 including power transmitting meansto synchronously adjust the valve cylinders of each pressure lockingmeans between a closed operating position and an open threadingposition.

13. Apparatus as claimed in claim 1 including a jet injector meansmounted at; the outlet end of each elongated treatment chamber forrethreading a filamentary bundle through said chamber and its associatedflow duct members.

14. Apparatus as claimed in claim 1 wherein said elongated treatmentchambers as substantially straight pressure pipes are mounted within aclosed heating box equipped with feed means to introduce said vaporousheating medium into the box, thereby externally heating said pipes atthe same temperature as in the treatment chambers.

15. Apparatus as claimed in claim 14 wherein said feed means for saidheating box is in fluid communication with said feed pipe means for eachtreatment chamber through a common vapor reservoir, and an individualshut-off valve is separately connected in the feed pipe for eachtreatment chamber.

16. Apparatus as claimed in claim 1 including a plurality ofsynchronously-operable, valve cylinder means partly intersecting theflow duct path of each pressure locking means, each of said cylindermeans being displaceable between a closed operating position and an openthreading position, and a plurality of cylindrical bores arrangedbetween adjacent valve cylinder means as intermediate turbulencechambers along and partly intersecting the flow duct path.

17. In an apparatus for the continuous heat treatment of a runningfilamentary material with a vaporous heating medium at an elevatedtemperature, said apparatus including a substantially enclosed elongatedheat treatment chamber in the form of a substantially straight pressurepipe having feed means for introducing the vaporous heating medium intothe pipe and an inlet and outlet at each end of the pipe to receive therunning filamentary material, the improvement which comprises:

a flow duct member arranged in direct fluid connection with thetreatment chamber at said inlet end and at said outlet end of said pipe;and

a pressure locking means in each flow duct member including at least onecylindrical valve throttling element rotatably mounted in the flow ductpath for adjustable rotation between a closed operating position ofminimum throttling cross-section effective to prevent leakage flow ofthe vaporous heating medium from said pipe and an open threadingposition of maximum throttling cross-section effective to permit rapidintroduction of said filamentary material to be treated.

18. An apparatus as claimed in Claim 17 including means tosimultaneously rotatably adjust the valve throttling elements at eachend of said pipe between said closed operating position and said openthreading position.

1. Apparatus for the continuous heat treatment of a plurality offilamentary bundles as a yarn or the like with a vaporous heating mediumat temperatures above 100*C., said apparatus comprising: a plurality ofsubstantially closed elongated treatment chambers corresponding innumber to the number of filamentary bundles being treated, each chamberbeing substantially in the form of a straight pressure pipe over most ofits length, all of said pipes being arranged at lateral intervals apartfrom one another on substantially parallel axes; separate feed pipemeans for introduction of the vaporous heating medium into eachtreatment chamber; and two flow duct members including pressure lockingmeans for each treatment chamber, one duct member being arranged at theinlet end of said chamber and the other at the outlet end thereof sothat each is in direct fluid connection with the treatment chamber, saidpressure locking means comprising a plurality of rotatably mounted valvecylinders which penetrate at about right angles into the flow duct pathwhile being arranged in a row one behind the other on parallel axes ofrotation lying in about the same plane, each valve cylinder beingvariably recessed at the point of intersection with the flow duct toalter the cross-section of the flow path upon rotation of the valvecylinder.
 2. Apparatus as claimed in Claim 1 wherein four to six valvecylinders are arranged along said flow duct path for each pressurelocking means.
 3. Apparatus as claimed in claim 1 wherein each of saidvalve cylinders has a first arcuate or partially cylindrical recess onone side thereof with a depth corresponding approximately to thediameter of the flow duct path together with an adjoining narrower slotrecess extending at an acute angle from said first recess from a poIntspaced sufficiently inwardly from the outer circumference of the valvecylinder to provide a small working opening at the common junction ofthe two recesses.
 4. Apparatus as claimed in claim 3 wherein each ofsaid valve cylinders has a diameter which is approximately twice thediameter of the flow duct path.
 5. Apparatus as claimed in claim 3wherein the plane of the axes of rotation of said valve cylinders isoffset to one side of the axis of the flow duct path.
 6. Apparatus asclaimed in claim 4 wherein the plane of the axes of rotation of saidvalve cylinders is offset to one side of the axis of the flow duct pathat a distance of approximately the radius of said flow duct path. 7.Apparatus as claimed in claim 3 wherein said working opening at thecommon junction of the two recesses in each valve cylinder is about 2.0to 3.5 times greater than the cross-section of the yarn being treated.8. Apparatus as claimed in claim 1 including at least one turbulencechamber which is arranged along the flow duct path between two adjacentvalve cylinders.
 9. Apparatus as claimed in claim 8 wherein eachturbulence chamber is formed by a bore extending substantiallyperpendicularly and at least partly intersecting the flow duct path. 10.Apparatus as claimed in claim 9 having a plurality of said bores formingturbulence chambers alternately between adjacent valve cylinders, saidturbulence chambers being substantially equal in diameter to said valvecylinders and said turbulence chambers and said valve cylinders beingarranged with their axes lying in separate parallel planes offset andsymmetrical to the axis of the flow duct path.
 11. Apparatus as claimedin Claim 1 including means to simultaneously adjust the valve cylindersof said pressure locking means between a closed operating position andan open threading position.
 12. Apparatus as claimed in claim 1including power transmitting means to synchronously adjust the valvecylinders of each pressure locking means between a closed operatingposition and an open threading position.
 13. Apparatus as claimed inclaim 1 including a jet injector means mounted at the outlet end of eachelongated treatment chamber for rethreading a filamentary bundle throughsaid chamber and its associated flow duct members.
 14. Apparatus asclaimed in claim 1 wherein said elongated treatment chambers assubstantially straight pressure pipes are mounted within a closedheating box equipped with feed means to introduce said vaporous heatingmedium into the box, thereby externally heating said pipes at the sametemperature as in the treatment chambers.
 15. Apparatus as claimed inclaim 14 wherein said feed means for said heating box is in fluidcommunication with said feed pipe means for each treatment chamberthrough a common vapor reservoir, and an individual shut-off valve isseparately connected in the feed pipe for each treatment chamber. 16.Apparatus as claimed in claim 1 including a plurality ofsynchronously-operable, valve cylinder means partly intersecting theflow duct path of each pressure locking means, each of said cylindermeans being displaceable between a closed operating position and an openthreading position, and a plurality of cylindrical bores arrangedbetween adjacent valve cylinder means as intermediate turbulencechambers along and partly intersecting the flow duct path.
 17. In anapparatus for the continuous heat treatment of a running filamentarymaterial with a vaporous heating medium at an elevated temperature, saidapparatus including a substantially enclosed elongated heat treatmentchamber in the form of a substantially straight pressure pipe havingfeed means for introducing the vaporous heating medium into the pipe andan inlet and outlet at each end of the pipe to receive the runningfilamentary material, the improvement which comprises: a flow ductmember arranged in direct fluid connection with the treatment chamber atsaid inlet end and at said ouTlet end of said pipe; and a pressurelocking means in each flow duct member including at least onecylindrical valve throttling element rotatably mounted in the flow ductpath for adjustable rotation between a closed operating position ofminimum throttling cross-section effective to prevent leakage flow ofthe vaporous heating medium from said pipe and an open threadingposition of maximum throttling cross-section effective to permit rapidintroduction of said filamentary material to be treated.
 18. Anapparatus as claimed in Claim 17 including means to simultaneouslyrotatably adjust the valve throttling elements at each end of said pipebetween said closed operating position and said open threading position.